Fluting Casting | KUKA Endeffector
by Markus8100 in Circuits > Arduino
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Fluting Casting | KUKA Endeffector
"Fluting Casting" describes a modern design approach that mixes the Vitruv's column order in a digital fabrication way to adapt it to current needs in architecture.
In this Instructable, we will build a KUKA end-effector with the goal of material sensing and manipulation.
The project was conducted as part of the Computational Design and Digital Fabrication seminar in the ITECH masters program.
Supplies
Setup
The Arduino-controlled electrical part checks the casting material, which consists of plaster and expanded clay.
Our formwork material is TPU. It is a weldable thermoplastic polyurethane and is used for the pneumatic pavilion at the IBK Institute of the University of Stuttgart.
Proof of Concept
Reference
Our main reference is a project at the Swiss Federal Institute of Technology in Zurich called "Smart Dynamic Casting", in which a concrete column is continuously extruded as the concrete hardens.
This is made possible by the addition of substances that accelerate the curing process.
In this example, the column is formed on the move.
Conceptual Realisation
When it comes to conceptual implementation, it is all about sensing.
Firstly, sensing the air pressure to maintain the correct pressure in the formwork.
The second is measuring the temperature of the object. This tells us when the plaster has hardened, so that the KUKA can go into action.
Hands-on Material Testing
To prove our concept, we built the pneumatic formwork with a length of 50 cm and a diameter of 30 cm.
We prepared the plaster, mixed it with expanded clay and poured it into the inflated formwork. After 8 to 10 minutes you can feel the heat of the almost cured plaster.
Later on, in order to save on material, we added a pneumatic formwork on the inside.
Endeffector
The end-effector is divided into three stages. It is constrained within three wooden plates and four metal bars as a rig.
While the top plate is bolted to the KUKA SWS, the first stage contains the electronic devices, such as the Arduino.
The middle section has an offset of 30cm. This allows for easy casting into the last section, the pneumatic framework.
Addons
Simulacrum:
Simulacrum is a plugin for grasshopper, made by: Nicolas Kubail Kalousdian and Simon Lut.
Read and write global variables to a KUKA Robot arm using KukaVarProxy, directly from Grasshopper.
Firefly:
Firefly is the second mayor Addon used in this project. It enabled us to send commands to the Arduino directly from grasshopper. For using this function a special code has to be uploaded to the Arduino.
Arduino Code
As a brief explanation of the code, we are constantly updating the values of the sensors.
We can see if it is cured or not. The KUKA can only continue when the formwork is "fully deflated" and this is printed on the serial monitor.
Downloads
Serial Communication
We are using Firefly to bridge the gap between Arduino and Grasshopper and to read those values.
In order to communicate with the KUKA, we have worked a lot with bool variables.
“GoToPoint” is as signal, that is send to the KUKA and “WentToPoint” is another variable that received from the Arduino.
Result
You can see the fluting of our column quite well. It is good practice to start with a thin layer of plaster to avoid mess and to have a solid base.
Outlook
In the future, we could pump the cast material instead of filling it in by hand.
In addition, a distance sensor would help us to check how far the mould has been filled. This would determine how far the KUKA could go in one step.
A further next step would be that, because the formwork is adjustable and movable, we would also be able to produce curved free-form columns.